Many building structures have people, equipment, and lighting requiring energy or power for environmental comfort, work operations, visual acuity and safety, refrigeration and other purposes. These buildings are frequently divided into zones having separate heating, ventilating, and air-conditioning apparatus for each zone, and environmental condition monitors are provided for enabling the HVAC (heating, ventilating, and air-conditioning) apparatus to be operated automatically as needed for maintaining the environmental conditions desired in each of the zones.
Family-type restaurants serving steaks or seafood are typical of such buildings, which may have two or more dining areas, a kitchen area, a serving area, HVAC apparatus for each area, significant refrigeration equipment, extensive indoor and outdoor lighting, and assorted other apparatus requiring various schedules of operation and having various degrees of loading. Such apparatus and equipment is normally electrically powered and controlled, and it is preferable for the controls to be automatic under normal circumstances and that much of the apparatus should be turned off completely during certain hours of the day or night to eliminate waste of energy. Also, since electrical utility companies set their rates according to the peak demand load required by the customer, it is desirable to have controls for monitoring the demand load and for shedding electrical loads at a predetermined demand so that the peak demand cannot exceed a certain level as predetermined by correlation of electrical rates and the apparatus which must be maintained in operation at all costs.
Much of the apparatus is not needed at certain times of the day, and it is desirable to have automatic programs to assure that this apparatus is not inadvertently operated during those times; for instance, parking lot lights need not operate in the daytime, cooking equipment need not operate while the restaurant is closed, and the HVAC apparatus may be turned off when the restaurant closes and should be restarted shortly before opening.
Very sophisticated control equipment is commercially available for the aforementioned control functions, as well as for the automatic environmental control functions which maintain comfort conditions in the HVAC zones. Controls for performing the above described functions, as well as many others, are available from HONEYWELL, INC., Minneapolis, Minn., and certain of these functions are described in more detail in the description hereinafter of the preferred embodiment of the present invention. Honeywell W977 Management Systems, W972B Watt Transducers, W973 Single-zone Logic Panels, W974 Setback/Setup Modules, and T7047C Electric Thermostats and T7067B Transmitters therefor are items representative of the sophisticated control equipment available. Other commercially available control apparatus such as electronic humidistats, modulating valve and damper actuators, filter condition sensors, air flow sensors, and assorted other control elements are well known in the HVAC art for use with the more sophisticated controls.
However, while the above-mentioned controls have been available and in use in various customer- or contractor-designed applications, they have never been combined and utilized according to the present invention, in which a standardized control panel combines the circuitry, functions, indicating elements, and controls therefor in a central location at which predetermined load time programs and load limits can be set, controlled, and observed for the entire energy supply system of a multi-zoned, multi-load building structure. Such standardization and centralization is highly efficient for initial design and allows the manager of the building structure to maintain complete control over the structure without great technical expertise or burden on his time. Not only does the panel of the present invention provide pre-programmed control during normal operations but also allows management-by-exception when certain apparatus needs to be operated contrary to the time-programming, and provides for management observation of outdoor temperature at the panel, as well as of indoor temperature in each monitored zone by reading the signals from the same monitoring elements that control the automatic operation of the HVAC apparatus for each zone.